1. Field of the Invention
The present invention relates to a reproducing apparatus.
2. Description of Related Art
Some of known recording-and-reproducing apparatuses are arranged to record moving image data, as digital data, on a recording medium such as a tape or a disk. The apparatus of this kind generally digitizes an image signal, transforms the digital data from a two-dimensional spatial form into a two-dimensional frequency axis form by carrying out DCT (discrete cosine orthogonal transform) or the like, quantizes the transformed data, performs a variable length coding process on the quantized data, performs, on the coded data, further processes necessary for recording, such as an error correcting process, and then records the processed data on a recording medium, such as a disk, a tape or the like.
In reproducing the record of moving image data, reproduced data read out from the recording medium, such as a disk, is subjected to an error correction process and a variable length code decoding process. The decoded data is inversely quantized. The inversely-quantized data is subjected to an inverse DCT process to obtain image data decoded on two-dimensional spatial axes. The image data thus obtained is displayed on a TV monitor, a liquid crystal display monitor or the like.
The capacity of recording media, particularly, disk-shaped media, has rapidly come to increase these days. As a result, apparatuses have come to be capable of recording and reproducing not only audio signals but also video signals over a long period of time. For example, a recording format based on a high efficiency coding process, such as MPEG, is considered to be used for an image recording-and-reproducing apparatus capable of recording images for at least one hour at a data compressing rate of 4 Mbps to 10 Mbps or thereabout. The disk-shaped media are trending to have smaller size and a larger capacity. In view of this trend, image recording-and-reproducing apparatuses are being arranged to further increase the density of recording.
Some known image recording-and-reproducing apparatuses now use the MPEG coding system or the like.
It is conceivable that, in viewing moving images recorded on a recording medium, a search reproduction is made to find beforehand what is recorded on the recording medium. In making a search for some moving image data recorded on a disk-shaped medium, reproduction is made by deciding a feeding amount of tracks of the recording medium according to a set reproduction speed which is, for example, set by the user. The images reproduced are displayed on a TV monitor, a liquid crystal display monitor or the like, and are viewed by the user.
However, in the case of the apparatus arranged as mentioned above, during the search, the reproduction is made with the feeding amount of tracks of the recording medium decided according to the set reproduction speed, irrespective of motions of images or changes of scenes.
Therefore, in cases where there are fast motions of images or much changes of scenes, it is difficult to grasp the contents of the recorded image because of insufficient correlation between scenes or because of excessively fast changes of scenes on display. Further, in the cases of images which little move and scenes which little change, on the other hand, pictures on display do not change, thereby causing the user to feel that the search is taking an unnecessarily long waiting time before finding the contents of the image recorded on the recording medium.
The invention is directed to the solution of the above-stated problem.
It is, therefore, an object of the invention to provide a reproducing apparatus which is arranged to be capable of reproducing an image at an appropriate reproduction speed according to the motions of images obtained at the time of reproduction made for a search or the like.
It is another object of the invention to provide a reproducing apparatus arranged to be capable of performing a special reproduction, such as reproduction for a search (search reproduction), at such an appropriate reproduction speed as to make the contents of a reproduced image easily graspable.
To attain the above objects, in accordance with an aspect of the invention, there is provided a reproducing apparatus, which comprises reproducing means for reproducing from a recording medium a data string including image data and motion data indicative of motion of an image related to the image data, and control means for controlling a speed of reproduction of the image data by the reproducing means according to the motion data included in the data string reproduced by the reproducing means.
These and other objects and features of the invention will become apparent from the following detailed description of preferred embodiments thereof taken in connection with the accompanying drawings.